Transcript An Introduction to Visual Basic

An Introduction to Visual Basic
Terms & Concepts
What is VB?
• Visual Basic is a programming language
(actually an environment) designed to
create computer programs that run in
Microsoft Windows.
• VB has been developed through many
versions. This course uses VB 2008.
Getting Started
VB 2008 addresses problem solving
“from the outside, in.”
In other words, the user interface is designed
and created first, then it’s Events are
programmed.
The Windows GUI
• The Graphical User Interface is the means
through which users can interact with
programs.
• Each window is called a form.
• Each form is populated with controls.
• It is through these controls that the
programmer handles I/O in VB.
The Windows GUI
• There are many different kinds of controls:
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Label
Text box
Radio button
Check box
Command button
Image
List box
Drop-down list
Frame
Line / Shape
Tab
A Sample Form
Tab
Checkbox
Drop-down
list
Label
Textbox
Command
Button
Programming Language
Paradigms
Recall the programming paradigms:
• Procedural
• Functional
• Declarative
• Object-oriented
– Event-driven
In this paradigm we develop projects rather than programs.
Object Oriented Programming
A VB project consists of:
– Objects - the nouns of OOP
• forms and controls are examples of objects.
– Properties - the adjectives
• size, location, name, caption
– Methods - the verbs
• Move, Print, Resize, Clear
The dot operator
– Object.property is the syntax for referring to a
particular property of a particular object.